Constant-velocity joints are angularly coupled to wheel hub/bearing assemblies to transmit a rotary motion from a half-shaft engaged in the joint to a wheel supported by the wheel hub/bearing assembly, and operate in environments which are exposed to a particular degree to external agents, such as powder, debris, dirt and water.
Customarily, constant-velocity joints comprise an outer ring which is provided with a shaft inserted inside the wheel hub and coupled angularly to said wheel hub by means of a grooved profile. The bearing of the wheel hub/bearing assembly is, on the other hand, mounted on the wheel hub, or is provided with a flanged inner ring within which the shaft of the joint engages. In both cases, the bearing, or at least an intermediate space between an inner ring and an outer ring of said bearing, faces completely towards the outer ring of the joint, and therefore is completely exposed to the action of the external agents mentioned. To avoid the admission of impurities into the bearing, the latter is equipped with a sealing device mounted between the two rings so as to close the intermediate space, but the direct and constant exposure to the action of the external agents can bring about premature wear of the sealing device, in such a way that it may even lead to the infiltration of said agents into the area of coupling between the wheel hub and the shaft.
It is an object of the present invention to provide a protective screen for constant-velocity joints which not only makes it possible to protect the sealing device from the external agents, prolonging the service life, but can also be easily mounted on the constant-velocity joint irrespective of the manufacturing tolerances of said constant-velocity joint.